Cats leave meals unfinished not merely because they’ll full, but sometimes because of the meal’s scent:
A research group led by Professor Masao Miyazaki at Iwate University, Japan, has now shown that domestic cats may stop eating not only because they are full, but also because smell plays an important role in regulating feeding motivation. The study suggests that feeding behavior in cats is dynamically influenced by olfactory habituation and dishabituation. The study was published in Physiology & Behavior.
[…]In further experiments, the researchers tested whether the decline in intake caused by repeated presentation of the same food could be reversed by introducing a different food. Cats were given the same food for five consecutive trials and a different food in the sixth. Intake decreased significantly from the first to the fifth trial, but increased again when a new food was introduced, regardless of whether it was more or less palatable than the original one.
Remarkably, even without changing the food itself, simply introducing the odor of a different food restored intake. The researchers also found that continuous exposure to the same food odor between feeding cycles led to a further reduction in subsequent food intake. However, this effect was mitigated when a different odor was introduced during the intervals.
See Rachel Gordon, Why Cats Often Leave Food Behind Even When They’re Not Full, PHYS.ORG, Apr. 9, 2026.